>>Imagine ur cell battery is very low,u r expecting an important call and u don't have a charger.
Nokia instrument comes with a reserve battery. To activate, key is"*3370#"
Ur cell will restart with this reserve and ur instrument will show a 50% incerase in battery.
This reserve will get charged when u charge ur cell next time.
*3370# Activate Enhanced Full Rate Codec(EFR)
-Your phone uses the best sound quality but talk time is reduced by approx 5%
#3370# Deactivate Enhanced Full Rate Codec( EFR)
*#4720# Activate Half Rate Codec - Your phone uses a lower quality sound
but you should gain approx 30% more Talk Time
ivate Half Rate Codec